Q. The Sun rotates around its centre once in 27 days. What will be the period of revolution if the Sun were to expand to twice its present radius without any external influence? Assume the Sun to be a sphere of uniform density.
A) 100 days
B) 105 days
C) 115 days
D) 108 days
Explanation
[Solution by Claude - not from source] Angular momentum is conserved: $\frac25MR^2\omega=$ const, so $\omega\propto1/R^2$ and $T\propto R^2$. $T=27\times4=108$ days. Answer (4).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.